Hitherto, there are used discs such as optical disc or magneto-optical disc, etc. as recording medium of information signals.
In the disc of this kind, there are discs in which loading with respect to disc recording and/or reproducing unit is carried out by the disc alone and there are discs in which disc is accommodated within the disc cartridge and loading with respect to the disc recording and/or reproducing unit is carried out in the state where the disc is accommodated within this disc cartridge.
As disc recording and/or reproducing unit adapted for carrying out loading by the disc alone without being accommodated into the disc cartridge, there are used disc recording and/or reproducing unit of the tray loading system using disc tray.
The disc recording and/or reproducing unit of the tray loading system comprises, as shown in FIG. 1, a disc tray 203 for carrying out loading of disc 202 handled by the disc alone with respect to the unit body 201. The disc tray 203 is adapted so that a recess shaped disc mounting portion 204 on which the disc 202 is mounted is provided at one surface side, and is provided so that it can be moved within the range between a first position at which the disc mounting portion 204 is projected toward the external of the unit body 201 through an opening portion 205 provided at the unit body 201 and a second position in which the disc mounting portion is accommodated within the unit body 201.
In order to carry out loading of the disc 202, the disc tray 203 is moved from the unit body 201 to the first position of the external of the unit body 201 to mount the disc 202 on the disc mounting portion 204. Then, the disc tray 203 is moved to the second position within the unit body 201, whereby the disc 202 mounted on the disc mounting portion 204 is caused to undergo loading with respect to the recording and/or reproducing unit provided within the unit body 201.
In this way, in the disc recording and/or reproducing apparatus adapted so that disc 202 is caused to undergo loading by the disc alone, there is the possibility that disc 202 may be damaged during loading. When the disc 202 is damaged, missing in recording/reproduction of information signals is caused to take place.
In order to realize protection of the disc 202, a disc cartridge 211 adapted for accommodating this disc 202 is used. This disc cartridge 211 serves to exchangeably accommodate the disc 202, and comprises, as shown in FIG. 2, a cartridge body 212 for accommodating the disc 202, and a cover body 214 for opening/closing the opened side for carrying out insertion/withdrawal of disc 202 provided at the cartridge body 212. At a bottom surface portion 212a of the cartridge body 212, a disc mounting portion 215 on which disc 202 is mounted is provided, and the disc 202 is accommodated in the state mounted on the disc mounting portion 215. At the bottom surface portion 212a of the cartridge body 212, there is provided an opening portion 216 for allowing the portion extending from the central portion of the disc 202 toward the outer circumferential side to be faced to the external. The disc 202 accommodated within this disc cartridge 211 can be desirably exchanged by opening the cover body 214.
As the disc recording and/or reproducing apparatus using the disc cartridge 211 which has accommodated the disc 202 in this way, there is used an apparatus of the slot-in system which can directly carry out loading of the disc cartridge 211 into the unit body without using the disc tray. As shown in FIG. 3, this disc recording and/or reproducing apparatus of the slot-in system serves to carry out loading of the disc cartridge 211 through a cartridge insertion/withdrawal hole 222 provided at the front side of the unit body 221.
Meanwhile, there are instances where user desires to carry out loading by the disc alone in order to realize promptly or easiness of loading operation in discs of a certain kind such as optical disc of the reproduction only type, etc. In view of the above, there has been proposed a disc recording and/or reproducing apparatus which permits disc 202 to undergo loading by disc alone along with disc cartridge 211 which has accommodated the disc 202 therewithin. This disc recording and/or reproducing apparatus is the apparatus employing the tray loading system. As shown in FIG. 4, this disc recording/reproducing apparatus includes a disc tray 232 provided with a cartridge mounting portion 231 on which disc 202 or disc cartridge 211 can be mounted. This disc tray 232 is movably disposed within the range between first position at which cartridge mounting portion 231 provided at one surface side is projected toward the external of the unit body 234 and second position at which the cartridge loading portion 231 is accommodated within the unit body 234.
In this disc recording and/or reproducing apparatus, in order to allow disc cartridge 211 which has accommodated the disc 202 to undergo loading, disc cartridge 211 is mounted on the cartridge mounting portion 231 to move the disc tray 232 to second position within the unit body 233, whereby the disc cartridge 211 mounted on the cartridge mounting portion 231 is loaded with respect to the cartridge loading portion within the unit body 234 so that disc 202 accommodated within the disc cartridge 211 is loaded with respect to the recording and/or reproducing unit.
Moreover, in the case where the disc 202 is loaded by disc alone, disc 202 is mounted on the disc mounting portion provided within the cartridge loading portion 231 to move the disc tray 232 to the second position within the unit body 233, whereby the disc 202 mounted on the disc mounting portion is loaded with respect to the recording and/or reproducing section provided within the unit body 234.
Both the disc alone and the cartridge are permitted to undergo loading, whereby loading corresponding to kind of disc can be selected. Thus, improvement in the operability can be realized. However, in the case of carrying out loading of disc without accommodating it into the disc cartridge, it is difficult to prevent attachment of dust onto the disc thus to securely prevent so that the disc is damaged.
In order to realize reliable protection of the disc, it is desirable to accommodate it within the disc cartridge.
Meanwhile, in the disc cartridge 211 which has exchangeably accommodated the above-described disc 202, in order to carry out exchange of the disc 202, it is necessary to once eject the disc from the disc recording and/or reproducing unit to carry out opening/closing operation of the cover body 214 to carry out exchange with other disc 202. As a result, the exchange work becomes complicated.
In order to reduce the exchange work of the disc 202 or to eliminate such exchange work, it is necessary to prepare disc cartridges 211 corresponding to the number of discs 202. As a result, a large space is required for storage of the disc 202.